Grundfos CH, Инструкция по установке и эксплуатации

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The electrical connections should be in accordance
with the diagrams on pages 92 and 93.
4. Adjustment
Sets which are ready-mounted on delivery have the
following presettings:
4.1 Calculation of cut-in/cut-out pressures
The cut-in pressure is the sum of:
• minimum pressure required at the highest tap,
• delivery head from the pump to the highest tap,
• pressure loss in the pipes.
Recommended cut-out pressure:
cut-in pr 1.0-1.5 bar.
Note: The cut-out pressure must not exceed the
maximum discharge pressure of the pump.
In the case of JP pumps without an inlet pressure,
it is not advisable to fit the ejector valve. If fitted,
the valve
must be in pos. 1.
If a JP pump is used as a booster pump (pump with
inlet pressure), the ejector valve can be turned to
any position.
If the pump does not stop when no water is con-
sumed, turn the ejector valve to a lower position.
4.2 Adjustment of tank precharge pressure
When the pump cut-in pressure has been deter-
mined, the required precharge pressure of the dia-
phragm tank can be calculated. The precharge pres-
sure must be adjusted to a value of 90% of the cut-in
pressure.
When adjusting/reading the precharge pressure, be
certain that there is no water pressure on the dia-
phragm tank from the pipework.
Note: An adjustment of the pressure switch setting
also requires an adjustment of the precharge pres-
sure of the diaphragm tank.
See the installation and operating instructions for the
diaphragm tank.
4.3 Setting of pressure switch
Under no circumstances must the cut-out pressure
be higher than the maximum operating pressure of
the pump and tank.
Remove the cover from the pressure switch to reveal
the adjusting screws, see fig. 2.
Fig. 2
If another pressure switch setting is desired, proceed
as follows:
Setting the cut-in pressure:
1. Turn the screw B clockwise to reduce the cut-in
pressure.
Turn the screw B counter-clockwise to increase
the cut-in pressure.
The differential pressure range is widened and
narrowed respectively.
2. Start the pump and check by reading the pres-
sure gauge whether the desired cut-out and cut-
in pressures have been obtained.
Setting the cut-out pressure:
1. Turn the screw A clockwise to increase the cut-
out pressure.
Turn the screw A counter-clockwise to reduce the
cut-out pressure.
The differential pressure range remains
unchanged.
2. Start the pump and check by reading the pres-
sure gauge whether the desired cut-out and cut-
in pressures have been obtained.
If the booster set has a supply cable with-
out a plug, the set must
either be
equipped with a supply cable with a plug
or be connected to the installation by
means of a mains switch with a minimum
contact cap of 3 mm in all poles.
The switch must be suitable for frequent
operation.
Type p
tank
p
cut-in
p
cut-out
CH 2-30 1.3 bar 1.5 bar 2.5 bar
CH 4-30 1.0 bar 1.1 bar 2.2 bar
CH 4-40 2.0 bar 2.2 bar 3.2 bar
Other CH
and JP
types
1.9 bar 2.2 bar 3.3 bar
Because of shock hazard, the booster set
must be off circuit when the cover of the
pressure switch is removed.
When the pressure switch has reached the
cut-out pressure, the input terminals of the
pressure switch are still live. To avoid this
situation, the electricity supply must be
switched off.
TM
0
1
6
914
3
799
Adjust in order to
A move the differential pressure range.
B
widen/narrow the differential pressure
range.